1. Field of the Invention
This invention generally relates to automatic espresso coffee machines and, more particularly, to an improved device for loading, pressing, feeding and disposing off the ground coffee in automatic espresso coffee machines.
2. Description of the Prior Art
It is known that in the automatic espresso coffee machines, so called machines of integral type, all the operations for obtaining the espresso coffee are automatically carried out in a sequence.
Such machines comprise normally a coffee mill intended to grind the grains of coffee, a pump for the water, a boiler intended to produce hot water for the infusion of the coffee and a unit intended to prepare the espresso coffee.
This unit carries out all the operations for loading, pressing, feeding the ground coffee, infusing it, delivering the coffee infusion and disposing off the coffee grounds.
Normally, for carrying out these operations, the unit for preparing the espresso coffee contains all the elements for causing the movements for positioning the ground coffee in the various working stations. To this purpose, for feeding the ground coffee to the infusion station, a reciprocating carriage is provided which reciprocates from a coffee loading and disposal station to the coffee infusion station. This carriage is provided with a receptacle for receiving the ground coffee coming from the coffee mill in the loading station, moving it in the infusion station for preparing the coffee infusion and returning the coffee grounds in the loading station for the disposal of them.
In the loading station the ground coffee is to be pressed to the correct degree in order to be then transferred, in this pressed condition, to the coffee infusion station. For pressing, loading and disposing off the ground coffee a pressing piston is used.
The movements of the coffee feeding carriage and the coffee pressing piston are hydraulically or pneumatically controlled by rather complex means which can deteriorate and even be damaged, thereby requiring a frequent servicing and changing thereof. These disadvantages negatively affect both the manufacturing costs of the conventional espresso coffee machines and the life thereof.